Andy Waterworth grabbed a crucial winner to keep Linfield’s slim title hopes alive.
The big striker pounced midway through the second half to earn David Healy’s boys all three points.
Healy had to watch the match from the grandstand as he was handed a massive six game ban by the IFA.
Linfield almost took the lead on six minutes when Niall Quinn fired in a low cross form the left which was completely missed by Waterworth and Cameron Stewart.
That helped spark the Blues to life and little Paul Smyth was unfortunate to see his low drive deflected inches past the post with Elliott Morris beaten.
The action immediately switched to the other end and to took a wonderful goal line clearance from Reece Glendinning to prevent the home side taking the lead when he scooped away a Steven Gordon shot.
As the clocked ticked down to the interval, Morris produced a stunning save to deny Quinn and when the ball broke to Stephen Lowry, he drove his shot inches past.
The Blues roared from the traps after the half-time cuppa with Jimmy Callacher volleying a Quinn corner kick just over the top when he really should have hit the target.
And, they came agonisingly close again on 51 minutes. Waterworth headed down a Mattie Clarke cross for Smyth, whose fierce drive flashed right across the face of the goal.
The Bues finally made the breakthrough on 62 minutes. Skipper Jamie Mulgrew was flattened by an untidy challenge from Jonathan Smith and, when Glendinning whipped in the free kick, Stewart managed to get a touch before Waterworth rammed his shot past Morris -- his 19th of the season.
GLENTORAN: Morris, McAuley, Ferrin, Addis, Redman, Harmon (O’Flynn 87), McAlorum, Kane (Novo 65), Lavery, Gordon (Black 69), Smith. Subs not used: Nelson, Foley.
LINFIELD: Moore, Glendinning, Stafford, Callacher, Clake, Smyth (Gaynor 80), Lowry (Ward 69), Mulgrew, Quinn, Stewart (Burns 78), Waterworth. Subs not used: Casement, Carson.
REFEREE: Tim Marshall (Ivinestown)